Asphalt compositions



United States Patent ASPHALT COOSITIONS Lowell T. Crews, Homewood, and Mathew L. Kalinowski,

Chicago, Ill., assignors to Standard Oil Company, Chrcago, 111., a corporation of Indiana No Drawing. Application July 29, 1952, Serial No. 301,612

Claims. (Cl. 106-273) The present invention is directed to improvements in bitumen compositions, and particularly to improvements in mineral aggregate coating compositions, and more particularly relates to bitumen compositions having improved adherence to damp or wet mineral aggregates.

Residual oils and/or bituminous materials used in the preparation of pavements and roads do not coat and adhere well to mineral aggregates unless the aggregate is substantially dry, and for this reason, in conventional pavements or road construction practice, it is customary to dry the mineral aggregate by suitable well known methods. Furthermore, water entering the road or pavement during service may have a detrimental effect in that it may displace the oil or bitumen from the surface of the aggregate and thus diminish the bonding effect of the oil and/or bitumen. This materially shortens the life of the road or pavement requiring frequent repairs and is, therefore, uneconomical.

Mineral aggregates employed in road or pavement construction range in character from hydrophilic to hydrophobic. In general, siliceous and acidic minerals, such as sands and gravels, tend to be hydrophobic while calcareous, alkaline minerals, such as limestone, tend to be hydrophilic. It has been observed that the mineral aggregates appear to have a greater attraction for water than for oil or bitumens and that it is diflicult to obtain by conventional methods complete or satisfactory coating of aggregates by oil or bitumen when water is present. Furthermore, even though satisfactory coating isf btained by using dry aggregates, the oil or bitumen tends to be displaced if water enters the pavement or road.

It is known that the coating of damp or wet mineral aggregates by oil or bitumen may be effected and the resistance of the coating to displacement or stripping by water improved by treating the aggregate with small amounts of water-soluble soap of a fatty acid in conjunction with water-soluble salt of a polyvalent heavy metal or activator. For optimum results with these reagents the relative amounts of the two reagents must be carefully adjusted. Thus, when a divalent heavy metal is used as activator, the amount of soap used should be substantially one mole per mole of activator; with a trivalent metal between one and two moles of soap per mole of activator. Use of larger amounts of soap than this diminishes the effect obtained, and this decrease of efliect increases with excess of soap over the proportions given until when the amount of soap becomes equivalent to the activator, i. e., two moles of soap per mole of divalent metal or three per mole of trivalent metal, the beneficial effect of the reagent substantially disappears.

The above method has the disadvantage that the relative amounts of soap and polyvalent heavy metal activator are critical and must be carefully adjusted for optimum results. Use of an excess of soap over the optimum amount diminishes rather than enhances the effect obtained; the use of the excess heavy metal to avoid the Furthermore, the two reagents must be weighed or measured and added to each batch, as neither is soluble in the oil or bitumen; while this disadvantage may be partially overcome under favorable conditions by using in place of the soap a fatty acid dissolved in the oil or bitumen, this expedient is very effective only under favorable conditions of low moisture content of the aggregate, adequate and efficient mixing, etc. Under the conditions which are not at all severe, such as appreciable amounts of water and/ or facilities for only moderately efficient mixing, fatty acids appear not to be sufliciently soluble in water to reach and react with the heavy metal ion to the required extent, and if added directly to the mixture or dissolved in the oil or bitumen are practically without effect.

Another important disadvantage of the above method is that a heavy polyvalent metal salt must be used with the soap. Furthermore, it has been found that while some limestones appear capable of adsorbing or reacting with polyvalent heavy metal ions and accordingly respond to some degree to the above method, a great many others do not, and with these it is difficult or impossible to obtain a good coating by the above method. Also, since the foregoing method is not in general satisfactory with limestone, a great many natural mixed aggregates, such as gravels containing both siliceous and calcareous particles, will have only a portion of the particles coated.

It is an object of the present invention to provide a bituminous material having improved coating properties. It is also an object of the present invention to provide an oil or bitumen composition which will adhere to wetted mineral aggregates. Another object of the invention is to provide a coating composition for acidic and alkaline mineral aggregates which will not be stripped therefrom by aqueous liquids. Still another object of the invention is to provide a coating composition for acidic mineral aggregates which can be applied without the necessity of drying the mineral aggregate and which will adhere thereto even in a wet condition. Another object of the invention is to provide a method of preventing stripping of the coating composition from mineral aggregates by Water after the road and/ or pavement is constructed. A further object of the invention is to provide a method of promoting the adherence of oil bituminous materials to mineral aggregates without the necessity of drying the same. Other objects and advantages of the invention will become apparent from the following description thereof.

In accordance with the present invention bitumens such as for example road oils and asphalts having improved mineral aggregate coating properties are obtained by incorporating in such bitumens from about 0.25% to about 5%, and preferably from about 0.5% to about 3%, by volume, based on the bitumen content of an oil-soluble tertiary amine having the general formula:

in which R is an alkyl group of at least about 8 carbon atoms, and preferably from about 10 to about 20 carbon atoms, R is an ethylene or propylene radical, and x and y are integers, the sum of which is not greater than about 8, and preferably about 2 to about 5, inclusive. The aliphatic group, R, may be saturated or unsaturated, such as octyl, decyl, dodecyl, pentadecyl, hexadecyl, octadecyl radicals, etc. The tertiary amines of the present invention are suitably prepared by condensing an alkyl primary amine in which the alkyl radical is of desired carbon chain length with not more than about 8, and preferably 2 to 5, inclusive, moles of the ethylene oxide. The primary amine used may be a chemically pure amine or a commercial amine, such as the amines manufactured and marketed by Armour and Company under the trade names, Armeen 3 CD, Armeen SD, Armeen D, Armeen 16D, etc. Armeen CD and fArmeen SD .aremixtures of primary amines prepared from coconut oil and soybean oil, respectively, while the other Armeens are mixtures of primary amines containing-predominantly the number. of carbon atoms specified in the trade name.

Examples of tertiary amines suitable for use in the present invention are the amines manufactured and sold by Armour and Company underthe trade'names Ethomeen C, Ethomeen T, Ethomeen S and Ethomeen 18. These products are condensation products of a coca amine, tallow amine, soybean amine and stearylamine, respectively, with various proportions of ethylene oxide. The primary amines are obtained by converting fatty acids derived from natural fatty acid glycerides, into nitriles, and then reducing the nitriles to 'the primary amines at temperatures under 150 -C.'in the presence of an alkali. The tertiary aminesare obtained by condensing a primary amine with an alkylene oxide or a polymer of an alkylene oxide.

The asphalt component of the herein-described composition may be any bitumen which is useful for the coating of mineral aggregates used-in the making of roads or highways, etc., or for the coating of other materials or surfaces Where a water-resistant bond between the surface and the asphalt is advantageous or necessary. The term asphalt, as employed herein is intended to be synonymous with bitumenand to cover a liquid, semisolid or solid plastic bituminous material of the type employed in making or surfacing of highways and/or pavements, caulking agents, sealing compounds, water impervious paints, roofing materials, etc. Such asphalts or bituminous materials are mixtures of hydrocarbons of natural or pyrogenous origin, and are usually derived from petroleum or coal but may occur as such in nature. Asphalts may be derived as distillation residues -or by catalytic oxidation of residues, or by cracking residues with or without ainblowing. The specific example of an asphalt of the type usually employed in the preparation of highways, etc. is a petroleum residuum fiuxed with a light aromatic diluent boilingin the range of 400 F. to 700 F., to give a cutback product of the following specifications:

Cutback asphalt Flash, F. (C. O.'C.) NLT 150 Viscosity, f-urol at 140 F 100-200 A. S. T. M. distillation:

Percent 01f at 437 F NMT 10.0

Percent off at 500 F '15-55 I Percent offat 600 F 60-87 Residue at 680 F NLT 670 TESTS-ON DISTILLATION Residue A. S. T. M. penetration at 77 F 120-300 A. S. T. M. ductility at 77 F NLT 100 S01. in CCl4, percent NLT 99.5 Oliensis spot test Negative Normally solid paving asphalts of the 40200 penetration gradesv commonly used in road building fall within the following specifications:

Penetration at 77 F '40-200 A. S. T. M. ductility at 77 F NLT 1 100 Oliensis spot test Negative Solubility in CCl4, percent NLT 99.5 Specific gravity at 60 'F NLT 0990 1.000 Flash, F. (C. O. C.) NL'T 47S Loss on heating 50 grams for five hours at 325 F., percent 'NMT 0.5

Penetration ofresidue at '77" F.

percent of original penetration NLT 70-75 1 Not less than. Not more than.

line mineral aggregates.

The effectiveness of the herein-described tertiary amines in enhancing the adhesion of asphalts to wet mineral aggregates is demonstrated by the data in the following table obtained by subjecting blends of a cutback asphalt having the specifications described above, and various amounts of tertiary amines of the type described to the following test:

20 grams of Ottawa sand or 20 grams of a 20 to 35 mesh limestone are weighed into a 2 oz. container and covered with one-half inch distilled Water, the mixture then shaken for thirty seconds and the extent of coating determined by visual inspection; the results are expressed as percent coated.

The additives used in obtaining the data are identified as follows:

Additive -Condensation products of a coca amine and 5 moles of ethylene oxide.

Additive Condensation product of a coca amine and 10 moles of ethylene oxide.

Additive Condensation product of tallow amine and 2 moles of ethylene oxide.

Additive Condensation product of tallow amine and 10 moles of ethylene oxide.

Additive ECondensation product of octadecyl amine and 2 moles of ethylene oxide.

Additive -Condensation product of octadecylamine and 5 moles of ethylene oxide.

Additive GCondensation product of octadecyl amine and 10 moles of ethylene oxide.

Additive Condensation product of octadecyl and 15 moles of ethylene oxide.

Additive Condensation product of soybean and 2 moles of ethylene oxide.

Additive -Condensation product of soybean and 5 moles of ethylene oxide.

Additive --Condensation product of soybean and 10 moles of ethylene oxide.

Additive L-Condensation product of soybean and 15 moles of ethylene oxide.

amine amine amine amine amine Percent Coated Run N o. Additive Sand Limestone Control (No Additive) 0 Control 1% Fatty Amine 100 Control 1% A 100 Control A 100 Control A. Control 1% B-. 20 Control 1% C. Control %2% C. 80 Control 1% D... 25 Control 1% E 100 Control 80 Control 1% F. 100 Control F 80 Control 1% G. 10 Control 1% H 10 Control 1% I. 100 Control I 80 Control 1% .T. 1.00 Control M J 80 Control 1% K... 10 Control 1% L 5 1 Coca, tallow, octadecyl or soybean fatty amine.

The above data demonstrate that the condensation .products of long chain alkyl primary amines with at least 2. but less'than 10 moles of an alkylene oxide, such as .ethylene oxide, are eifective in enhancing thecoating properties of bitumens with respect to wet acidic and alkaline mineral aggregates. For acidic aggregates as little as of the additive is effective, while at least 11% of the additive isrequired-to effectively coat alka- The data further demonstrate that-the condensation products of the primary amines with 10 moles or moreof ethylene oxide are ineffective 'additive'for either acidic or alkaline mineral aggregates.

:Percentages expressed herein are volume percentages unless otherwise stated.

00 v-nm a 00 While the present invention has been described by reference to specific embodiments thereof, these are given by Way of illustration only and the invention is not to be limited thereto, but includes Within its scope such modifications and variations as come within the spirit of the appended claims.

We claim:

1. A non-aqueous composition of matter comprising a major proportion of a bitumen and from about 0.25% to about 5% of an oil-soluble tertiary amine having the general formula:

}R'0),H R-N \(R'O),,H in which R is an alkyl group of at least about 8 carbon atoms, R is an alkylene radical selected from the group consisting of ethylene and propylene and x and y are integers, the sum of which is at least 2 and not greater than about 5.

2. A bitumen composition described in claim 1 in which the tertiary amine has the general formula:

(CHzCH2O)=H (CHaOHgOhH in which R is is an alkyl group of at least about 8 carbon atoms, and x and y are integers, the sum of which is at least 2 and not greater than about 5.

3. A composition of matter described in claim 1 in which the tertiary amine has the general formula:

in which R is an alkyl radical of at least 8 carbon atoms derived from coconut oil, and x and y are integers, the sum of which is at least 2 and not more than 5.

4-. A composition of matter described in claim 1 in which the tertiary amine has the general formula:

)CHsCHaO) 1H R-N CHnCHzO) ,H in which R is an alkyl radical of at least 8 carbon atoms derived from tallow oil and x and y are integers, the sum of which is at least 2 and not more than 5-.

5. A composition of matter described in claim 1 in which the tertiary amine has the general formula:

)CHiOHZO) 1H R-N Romomoyn in which R is an alkyl radical of at least 8 carbon atoms derived from soybean oil, and x and y are integers, the sum of which is at least 2 and not more than 5.

6. A composition of matter as described in claim 1 in which the tertiary amine has the general formula:

/(CH2CH20):H R-N CHzCHzOMH in which R is an alkyl radical having 18 carbon atoms and x and y are integers, the sum of which is at least 2 and not more than 5.

7. A non-aqueous coating composition resistant to water-stripping comprising a major proportion of a normally liquid bitumen and from about 0.25% to about 5% of an oil-soluble tertiary amine having the general formula:

(R'o),,H

in which R is an alkyl group of at least about 8 carbon atoms, R is an alkylene radical selected from the group consisting of ethylene and propylene, and x and y are integers, the sum of which is at least 2 and not greater than about 5.

8. A non-aqueous coating composition comprising a major proportion of a cutback asphalt and from about 0.25% to about 5% of an oil-soluble tertiary amine having the general formula:

(R'0),H R-N/ (R'O) ,H in which R is an alkyl group of at least about 8 carbon atoms, R' is an alkylene radical selected from the group consisting of ethylene and propylene, and x and y are integers, the sum of which is at least 2 and not greater than about 5.

9. A non-aqueous coating composition comprising a major proportion of a normally solid paving asphalt and from about 0.25% to about 5% of an oil-soluble tertiary amine having the general formula:

in which R is an alkyl group of at least about 8 carbon atoms, R is an alkylene radical selected from the group consisting of ethylene and propylene, and x and y are integers, the sum of which is at least 2 and not greater than about 5.

10. A non-aqueous roadway construction material resistant to water stripping, comprising mineral aggregates admixed with a coating composition comprising a major proportion of a normally liquid bitumen and from about 0.25% to about 5% of an oil-soluble tertiary amine having the following general formula:

;R'0),H R-N in which R is an alkyl group of at least about 8 carbon atoms, R is an alkylene radical selected from the group consisting of ethylene and propylene, and x and y are integers, the sum of which is at least 2 and not greater than about 5.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A NON-AQUEOUS COMPOSITION OF MATTER COMPRISING A MAJOR PROPORTION OF A BITUMEN AND FROM ABOUT 0.25% TO ABOUT 5% OF AN OIL-SOLUBLE TERTIARY AMINE HAVING THE GENERAL FORMULA: 